Portable apparatus for drilling slim hole wells



P. SCOTT Oct. 25, 1966 PORTABLE APPARATUS FOR DRILLING SLIM HOLE WELLS Filed March 18, 1964 4 Sheets-Sheet 1 mm mm g Nm T m mm W L w P P. SCOTT Oct. 25, 1966 PORTABLE APPARATUS FOR DRILLING SLIM HOLE WELLS Filed March 18, 1964 4 Sheets-Sheet 2 P. SCOTT Oct. 25, 1966 PORTABLE APPARATUS FOR DRILLING SLIM HOLE WELLS Filed March 18. 1964 4 Sheets-Sheet 5 PA UL 500 TT INVENTOR.

Oct. 25, 1966 P. SCOTT 3,280,920

PORTABLE APPARATUS FOR DRILLING SLIM HOLE WELLS Filed March 18, 1964 4 Sheets-Sheet 4 United States Patent SLIM This invention relates to improvements in apparatus for drilling wells. It is particularly useful in drilling slanted wells but it is not limited to such use.

It is often desirable to drill wells at a substantial angle from the vertical, especially when drilling multiple wells from an olfshort drilling platform, drilling from a shore location to penetrate a formation beneath a body of Water, drilling around salt domes, drilling to intercept a Well that is on fire, and for other reasons. such slanted drilling has been accomplished in the past by use of whipstocks, knuckle joints, and other downhole equipment which may require many withdrawals of a drill string and setting of whipstocks, etc., to deflect the well to the desired inclination. Withdrawal of drill string and setting of downhole equipment to deflect the well is time consuming and requires highly skilled operators.

As drilling proceeds it is frequently necessary to add a section of pipe to the drill string. This is often accomplished by suspending the drill string in the bore hole from slips, suspending a section of pipe to be added vertically above the drill string by use of a pipe elevator carried by a traveling block, lowering the section of pipe into joint engaging position with the upper end of the drill string, and tightening the joint by the use of tongs.

In removing drill string from the bore hole a reverse procedure is used. The entire string is lifted by the pipe elevator to bring a joint in the drill string just above the drilling floor, slips are set to carry the weight of the drill string in the bore hole, the pipe is gripped with tongs adjacent to the joint above the drilling floor, and the section extending upward is broken out or unscrewed. The loosened section is then removed and is usually racked in upright position within the mast. These operations usually require the services of at least three men.

It is an object of this invention to provide improved apparatus for drilling wells which requires a reduced amount of time and labor in adding and removing sections of drill pipe from a drill string.

Another object is to provide a portable apparatus for drilling slim holes which can be operated by one man.

Another object is to provide an improved apparatus for drilling a well at a selected inclination from the vertical in which the inclination of the well is controlled from the surface of the earth.

Another object is to provide an improved apparatus for drilling wells which includes an improved means for adding a section of pipe to a string of drill pipe and removing sections from said string.

1 Another object is to provide an improved apparatus for drilling a well in which tongs are mounted on adjustable supports carried by a drill floor which is tiltable to and from horizontal positions.

Still another object is to provide an apparatus of the above type which is simple and cheap in construction and dependable .in operation.

Other objects, advantages and features of this invention will be apparent to one skilled in the art upon a consideration of the written specification, the attached claims and the annexed drawings.

In the present invention an apparatus for drilling wells is provided which includes a mast having an open side and a means for supporting a string of drill pipe rotatably. located within the mast. The supporting means preferwhen the frame is in upright position.

3,280,920 Patented Oct. 25, 1966 ably is a power swivel of the type which includes a sub carrying a standard API tool joint connection adapted to engage an upper end of a section of drill pipe, a motor, which may be of electric or hydraulic type, preferably hydraulic, connected to rotate the sub and suitable connections for passing drilling fluid through the swivel and drill string. The elements recited above are conventional in themselves but provide the background in which new elements are arranged.

A means for raising or lowering a string of drill pipe in rectilinear direction parallel to the longitudinal centerline of the mast without regard to the angle of inclination of the centerline is provided. This means is power operated and preferably includes a hydraulic cylinder connected through a suitable arrangement of lines and sheaves to apply positive force upon the power swivel tending to move the swivel upward or downward in a mast as desired. The swivel is mounted on a wheeled carriage which runs on suitable tracks carried by the mast.

A means for adding and withdrawing sections of drill pipe to and from the drill string is provided. This means preferably includes an elongate frame pivoted adjacent the lower end of the mast for swinging movement through said open side of the mast between a substantially horizontal position and an upright position with the upper end of the frame near the pipe supporting means in the mast and releasable clamps adapted to grip a section of drill pipe mounted on the frame for a limited longitudinal reciprocating movement thereon, in position to hold a section of drill pipe upright in alignment with the drill string This frame is power operated, preferably by hydraulic power, and the clamps also should be power operated.

When the frame is in substantially horizontal position a section of drill pipe to be added can be rolled into position where it may be grasped by the clamps. Then on elevation of the frame to upright position the section is brought into position to be attached to the drill string which will be held in slips carried by the drilling floor at this time. The section of drill pipe also is in alignment beneath the supporting means, preferably the sub of a power swivel, and since the clamps themselves are longitudinally movable on the frame the section of drill pipe may be lowered into joint engaging position with the string of drill pipe. The clamps are then released sufficiently that the pipe can be rotated and the joint is made up. The sub of the power swivel is attached to the upper end of the pipe and the slips are released, the frame is lowered into horizontal position and drilling is resumed.

The mast, slips and tongs are carried by a tiltably I mounted drilling floor so that drilling at any desired angle of inclination can be conducted by tilting the mast. The tongs preferably are mounted on adjustable supports spacing them from the drilling floor at controlled distance so that the upper end of the drill string does not have to be at the same distance from the drilling floor each time joints FIG. 4 is a detail of the tiltable drilling floor showing slips and power tongs carried thereon;

FIG. 5 is a schematic representation of a pivoted frame work carrying clamps; and

FIG. 6 is a fragmentary detail showing a preferred type of clamp and means for reciprocating the same on the frame of FIG. 5.

In FIG. 1 the reference numeral 5 designates generally a vehicle such as a trailer or truck, having mounted thereon a power means illustrated as an internal combustion engine 6 connected to drive a hydraulic pump 7 to maintain hydraulic fluid under pressure in a tank 8.

Fluid under pressure in tank 8 serves to operate the various hydr aulic cylinders shown, although the full system of lines connecting tank 8 and the various cylinders, have been omitted for purposes of clarity.

A mast 9, having an open side, preferably facing an end of trailer 5, is mounted on a tiltable drilling fioor 11, shown in detail in FIG. 4. An elongate frame designated generally as 12, is pivoted adjacent the bottom of mast 9 at 13 for swinging movement between a substantially horizontally position as illustrated and a position upright in the mast so that it swings through the open side of mast 9. The frame illustrated has an L type configuration, made up of the side 17 and a lateral extension therefrom, designated generally as 18, carrying clamps 19, shown in detail in FIG. 6. The clamps 19 are adapted to grip a section of drill pipe 21 illustrated in FIG. 6 as broken away parts 21a and 21b and 210. The clamps 19 are power operable preferably by hydraulic cylinders 24 having suitable connections 25 and 26 to fluid under pressure in tank 8. The clamps are also mounted for limited longitudinal movement on frame 12, illustrated as by sliding connections 27. Limited longitudinal reciprocating movement is imparted to clamps 19 by a hydraulic cylinder 28 having a connection 29 to the source of hydraulic fluid under pressure in tank 8.

The framework 12 is pivoted to swing into horizontal position adjacent to a pipe rack 23 carrying additional pipe joints 22 and preferably mounted upon a suitable vehicle as shown so that additional joints of pipe can easily be rolled into position to be grasped by the clamps 19.

The apparatus includes means within the mast for supporting a string of drill pipe rotatably, illustrated as a power swivel 31 or 31a shown in detail in FIG. 3. The particular power swivel 31a, illustrated in FIG. 3, includes a body 32 suspended from a traveling block 33 by bail 34. Motors 35 are carried by the body 32 and are arranged to drive the rotatable sub 36 having a threaded end 37 adapted to be connected to the upper end of a string of drill pipe through suitable gears enclosed within the body 32 (not shown). The swivel also includes a gooseneck connection 38 adapted to be connected to a mud hose 39 attached to stand pipe 41 shown only in FIG. 1 which cooperates with gooseneck 38 to provide a means for passing drilling fluid through the swivel and drill string to the bottom of the well. A means for raising and lowering the power swivel in rectilinear direction parallel the centerline of the mast, shown only in FIG. 3, is provided. This means includes lateral extensions 42 and 43 of the body 32 and traveling block 33 respectively carried by wheels 44 and 45 running in suitable tracks 46 illustrated as of U-shape in cross section. Tracks 46 are attached to the mast and are disposed parallel the centerline thereof so that the mast is inclined from the vertical, the track is also inclined to the same degree, and upward and downward travel of the block and power swivel are maintained in direction parallel to the centerline of the mast without regard to its angle of inclination.

Alternatively the power swivel 31 may be carried on lines arranged as illustrated in FIG. 2. This arrangement is preferable when very light weight drill string is being used as this arrangement provides for positive pressure upon the power swivel tending to move it in either upward or downward direction. In this arrangement illustrated in FIGS. 1 and 2 a hydraulic cylinder 47 is provided having connections 48 and 49 for hydraulic fluid under pressure from tank 8. A piston rod 51 is attached to a block 52 carrying a pair of sheaves 53 and 53a. A line designated generally as 56 having its opposite ends made fast to the mast at points 54 and 55 is reeved around the sheaves of 53 and 53a and around sheaves 57 and 58 carried by the mast in upper and lower positions as shown. An arm 59 extending outward from the body of power swivel 31 is attached to line 56 as shown in FIG. 2 and extends outward to be carried by wheels (not shown) corresponding wheels 44 shown in FIG. 3 and running in tracks corresponding to tracks 46.

The power swivel illustrated in FIG. 1 is operated by a hydraulic motor supplied with fluid under pressure from tank 8 through stand pipe and hose 6-2.

The mast 9 is carried upon a drilling floor 11 which is carried upon suitable pivots 63 (FIG. 4) and the floor may be tilted by operation of the hydraulic cylinder 64 having connections 66 to receive fluid under pressure from tank 8. The piston rod 67 of this cylinder is attached through a pivoted connection 68 to the mast, and operation of the cylinder 64 tilts the entire drilling floor and all elements mounted thereon through an angle controlled by the position of piston rod 67.

A set of power operable slips 69 is located about an opening 71 in the drilling floor in position to releasably grip a string of drill pipe 72 extending through opening 71. Power tongs 72, shown in retracted open position in FIG. 1, and closed around the pipe in FIG. 4, are mounted on adjustable supports 73 carried by the drilling floor. The supports 73 preferably include an upright standard and a slidable member 74 carried thereon so that the tongs 72 can be adjusted up and down as required to grip a section of drill pipe 75 to be added to or removed from the drill string 72. A guide 76 preferably is located below the drill floor and is attached thereto so that the guide opening 71, slips 69 and power tongs 72 will be in alignment with the drill string 72 at any angle of inclination of the mast and drilling floor.

Preferably all lines connecting tank 8 with the various hydraulic cylinders mentioned have control valve arranged at a single location 77 shown in FIG. 1, thus making the apparatus easily operable by one man.

It is believed that the opera-tion of the device will be evident from the above description. In beginning operation with the apparatus arranged as shown in FIG. 1 the apparatus is locate-d at the desired point for starting a well. The engine 6 is started and pressure rapidly builds up in :tank 8 as the result of the action of the pump 7.

The framework 12 is lowered to horizontal position and a joint of drill pipe is rolled into position to be grasped by clamps 19. A suitable drill bit is attached to the lower end of the section of drill string and that the section is swung into upright position in mast 9 by operation of cylinder 19. The power swivel 31 is attached to the upper end of the section of drill pipe, the clamps :19 are released and the frame 12 is swung into horizontal position into the open side of mast 9.

The mast 9 is tilted into desired inclination by operation of cylinder 64 which results in similar inclination of the drilling floor 11 rigidly attached to the mast. The power tongs 72 and slips 69 are in retracted open position at this time so that the drill bit may be easily inser-ted through the opening 71 in drill floor 11. Downward pressure is then applied to the power swivel 31 by operation of an hydraulic cylinder 49 and the drill bit is forced against the surface of the earth with the drill pipe at the desired inclination.

When the power swivel 31a arranged as shown in FIG. 3 is used, it is not necessary to exert downward pressuresince the Weight of the traveling block 33 and power swivel 32 will supply sufficient downward pressure to start the bit into the earth.

In either case drilling is continued until the upper end of the section of drill pipe approaches the level of the drilling floor. Rotation of the drill pipe is stopped at this position and the clips 69 are closed to support the drilling pipe extending downward into the bore hole.

The power swivel is then disengaged and raised to a level above that of the top of the new section of drill string to be added, the new section of drill string is rolled into position to be grasped by clamps 19 and frame 12 is swung upward through the open side of the mast to bring the new section of drill string in alignment with the drill string in the bore hole, and with the sub 36 carried by the power swivel.

The new section of drill string is then lowered into position for its threads to engage matching threads on the section in the bore hole, the clamps 19 are loosened sufliciently that the section of drill string can be rotated to start the joint and the power tongs 72 are advanced to close around the drill string. The power swivel is then lowered so that the threaded sections 37 of sub 36 engages the upper end of the section of drill pipe and then sub 36 is rotated sufficiently to make up the joint. Clamps 19 are then opened widely, the frame 12 is swung into horizontal position and drilling is resumed. This process is repeated whenever it is necessary to add a new section to the drill string.

In removing drill string from the bore hole the reverse process is used. The drill string is raised by elevation of the power swivel 31 or 31a so that the joint in the drill string is above the drilling floor. Slips 69 are closed to support drill pipe in the bore hole, the framework 12 is swung into upright position and the pipe between the joint and the power swivel is grasped by clamps 19. The power swivel is started in reverse to disengage sub 36 from the upper end of the section of pipe, power tongs 72 are advanced and closed around the section of pipe above the joint and the pipe is rotated suflicient to disengage the section from the drill string in the hole. The frame 12 is then lowered in to horizontal position, clamps 19 are released and the disengaged section is rolled out upon rack 32.

Many of the steps recited above need not be carried out in the stated sequence, but may be performed as is convenient to the operator. For example a new joint of pipe may be grasped by clamps while drilling is proceeding and sequence of other steps can be changed.

The apparatus described above is highly advantageous in reducing labor requirements in drilling wells to any depth. Within its intended limits of intended use, i.e., in comparatively shallow wells, control of angle of inclination of the well by tilting the mast is easily obtained. This feature is not intended to be used in extremely deep wells where the length of the drill string becomes so great that its flexibility permits a bit carried on the lower end of the drill string to follow a course principally due to gravity, variation in resistances encountered and other factors. No specific limit on depths where this feature is useful can be set, since this will depend on stiffness of the drill string, types of formations penetrated and other factors which vary from well to well, but in shallow drilling, as for example, drilling shot holes in a pattern, control of the angle of inclination of the well by tilting the mast is highly useful.

From the foregoing, it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth, together with other advantages which are obvious and which are inherent to the apparatus.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinat-ions. This is contemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

The invention having been described, what is claimed is:

1. An apparatus for drilling wells comprising in combination a mast; means for supporting a string of drill pipe rotatab'ly in the mast; means for raising and lowering the supporting means in rectilinear direction carried by the mast; and means for adding and withdrawing sections of pipe to and from said string of drill pipe, including an elongate frame pivoted adjacent the lower end of the mast for swinging movement with respect to the mast between a substantially horizontal position and an upright position with the upper end of the frame near the supporting means, and releasable clamps adapted to grip a section of drill pipe, means mounting the clamps on the frame for limited reciprocating movement longitudinally of the frame and in position to hold a section of drill pipe upright directly beneath said supporting means when the frame is in said upright position.

2. The apparatus of claim 1 wherein the means for supporting the string of drill pipe is a power swivel and the means for raising and lowering the supporting means includes tracks carried within the mast on which the power swivel moves up and down.

3. The apparatus of claim 2 wherein the mast is carried upon a tiltable drilling floor.

References Cited by the Examiner UNITED STATES PATENTS 1,829,304 10/1931 Schroeder 173-44 2,838,282 6/1958 Colquitt 173-147 2,956,782 10/1960 Mistrot 173--147 2,998,084 8/1961 Johnson et al. 1'7585 3,177,944 4/1965 Knights 2142.5 3,179,186 4/1965 Bull 173-147 3,193,116 7/1965 Kenneday et a1. 2142.5

FRED C. MATTERN, 111., Primary Examiner.

L. P. KESSLER, Assistant Examiner. 

1. AN APPARATUS FOR DRILLING WELLS COMPRISING IN COMBINATION A MAST; MEANS FOR SUPPORTING A STRING OF DRILL PIPE ROTATABLY IN THE MAST; MEANS FOR RAISING AND LOWER ING THE SUPPORTING MEANS IN RECTILINEAR DIRECTION CARRIED BY THE MAST; AND MEANS FOR ADDING AND WITHDRAWING SECTIONS OF PIPE TO AND FROM SAID STRING OF DRILL PIPE, INCLUDING AN ELONGATE FRAME PIVOTED ADJACENT THE LOWER END OF THE MAST FOR SWINGING MOVEMENT WITH RESPECT TO THE MAST BETWEEN A SUBSTANTIALLY HORIZONTAL POSITION AND AN UPRIGHT POSITION WITH THE UPPER END OF THE FRAME NEAR THE SUPPORTING MEANS, AND RELEASEABLE CLAMPS ADAPTED TO GRIP A SECTION OF DRILL PIPE, MEANS MOUNTING THE CLAMPS ON THE FRAME FOR LIMITED RECIPROCATING MOVEMENT LONGTUDINALLY OF THE FRAME AND IN POSTION TO HOLD A SECTION OF DRILL PIPE UPRIGHT DIRECTLY BENEATH SAID SUPPORTING MEANS WHEN THE FRAME IS IN SAID UPRIGHT POSITION. 